Modulation-Noise-Free Continuously Tunable Single-Frequency CW Ti:Sapphire Laser With Intracavity-Locked Birefringent Etalon
Authors：Pixian Jin , Yongjie Xie, Xuechen Cao, Jing Su, Huadong Lu , and Kunchi Peng
We present a continuously tunable single-frequency continuous wave (CW) Ti:Sapphire (Ti:S) laser with modulationfree-locked intracavity lithium niobate (LiNbO3) birefringen etalon (BE), which is implemented by detecting the polarization state variation of the reflflected laser beam from the BE. After the BE is stably locked, the continuous frequency-scanning range up to 40 GHz is obtained within the tuning range of 300 nm while the resonator length of the Ti:S laser is continuously scanned. Because the modulation signal is unnecessary in the presented Ti:S laser system, the inflfluences of the extra modulation signal on the intensity noise as well as the frequency noise of the laser are thoroughly eliminated and the modulation-noise-free continuously tunable single-frequency CW Ti:S laser is successfully attained.
Realization of a continuous-wave single-frequency tunable Nd:CYA laser
Authors：Huiqi Yang , Pixian Jin , Jing Su , Xiaodong Xu , Jun Xu , and Huadong Lu
We demonstrate an all-solid-state continuous-wave (CW) single-frequency tunable 1.08 μm laser, which is realized by employing a disordered laser medium Nd:CaYAlO4 (Nd:CYA) crystal. The maximal output power of single-frequency 1.08 μm laser is 1 W. By rotating the incident angle of the intracavity etalon (IE), the maximal tuning range of 183.71 GHz is achieved. After the IE is locked to the oscillating longitudinal mode of the laser, the continuous tuning range of 60.72 GHz for 1.08 μm laser is achieved by scanning the cavity length. To the best of our knowledge, this is the first demonstration of a CW single-frequency widely tunable 1.08 μm laser based on Nd:CYA crystal.
Direct generation of a stable multi-beam pulsed 355 nm UV laser based on a micro-lens array
Authors：Jiao Wei , Pixian Jin , Xuechen Cao , Jing Su , Huadong Lu , and Kunchi Peng
Multi-beam laser processing is a very popular method to improve processing efficiency. For this purpose, a compact and stable multi-beam pulsed 355 nm ultraviolet (UV) laser based on a micro-lens array (MLA) is presented in this Letter. It is worth noting that the MLA is employed to act as the spatial splitter as well as the coupling lens. With assistance of the MLA, the 1064 nm laser and 532 nm laser are divided into four sub-beams and focused at different areas of the third-harmonic generation (THG) crystal. As a result, the multi-beam pulsed 355 nm UV laser is successfully generated inside the THG crystal. The measured pulse widths of four sub-beams are shorter than 9 ns. Especially, the generated four sub-beams have good long-term power stability benefitting from the employed MLA. We believe that the generated stable multi-beam 355 nm UV laser can meet the requirement of high-efficiency laser processing, and the presented method can also pave the way to generate stable and long-lived multi-beam UV lasers.
Low-intensity-noise single-frequency CW 1080 nm laser by employing a laser crystal with the small stimulated-emission cross section
Authors：Huiqi Yang, Hailong Wang, Jiaqi Song, Pixian Jin, Xiaodong Xu, Jun Xu, and Huadong Lu*
An effective approach to obtain a single-frequency laser with low intensity noise is presented in this paper, which is implemented by employing a gain medium with the small stimulated-emission cross section (SECS). When the adopted Nd:YAP (Nd:YAlO) gain medium with SECS of 4.610 cm is replaced by Nd:CYA (Nd:CaYAlO) gain medium with SECS of 1.0410 cm, the frequency of measured intensity noise reached shot noise limit obviously reduces from 2.49 to 1.5 MHz, which agrees well with the theoretical predictions. On this basis, a single-frequency continuous-wave (CW) Nd:CYA laser with low intensity noise is first achieved. The attained output power of the Nd:CYA laser is 1.12 W. The achieved single-frequency CW 1080 nm laser will satisfy the requirements of the squeezed and entangled light generation.